Tropaeolum pentaphyllum
totototo@telus.net (Thu, 16 Oct 2008 14:07:01 PDT)

On 13 Oct 08, at 14:58, D Anderson wrote:

These were grown from seeds two years ago and no blooms. What am I doing
wrong?

Some of the tuberous tropaeolums have a reputation for being erratic bloomers,
so I hope you're not surprised.

It may be that the tubers simply aren't old enough to flower; Tulipa sprengeri,
for example, takes five years or more from seed to flower even under good
conditions. No amount of dancing around in a grass skirt shaking a rattle while
wearing your witchdoctor's mask is going to speed it up.

Another possibility is the soil temperature it's been exposed to. If these
tubers were potted, they almost certainly experienced swings in soil
temperature they wouldn't have if planted out. Or maybe they simply got too
warm at some point. Or never got quite warm enough. or maybe they got a tad too
cold during the winter.

Being in Winnipeg, planting out is infeasible. Even plunging a pot in the
ground can lead to the tubers escaping through the drain holes and I'm sure
they won't survive a Winnipeg winter.

A possible clue: we have one grower here with a true green thumb and she has
shown pots of various tuberous tropaeolums several times in full flower. I
believe she keeps them in a small greenhouse.

Additional clue: scanning the first page of google results, one gets the
impression that the tuberous tropaeolums are generally sensitive to
overheating. Perhaps the "right" recipe is to keep the soil on the cool side
during the summer. This can be difficult with pot culture: the sun on the wide
of a pot can send the temperature inside soaring. And a pot I have of
Tropaeolum tuberosum 'Ken Aslet' (supposedly) withered away during the heat of
August even though it was placed in shade with only reflected light on the pot.

You must be doing something right since they're at least coming up in the
spring instead of sulking all summer. This suggests to me that the way you
handle them in the winter is okay, but the summertime treatment needs to be
changed.

Good luck!

--
Rodger Whitlock
Victoria, British Columbia, Canada
Maritime Zone 8, a cool Mediterranean climate
on beautiful Vancouver Island

http://maps.google.ca/maps/…